chore(package): update stylelint-config-standard to version 20.0.0

Closes #18

Author: greenkeeper[bot]

package.json

@@ -81,7 +81,7 @@
     "saucelabs": "^2.1.3",
     "selenium-webdriver": "^4.0.0-alpha.1",
     "shx": "^0.3.2",
-    "stylelint-config-standard": "^18.2.0",
+    "stylelint-config-standard": "^20.0.0",
     "supertest": "^4.0.2"
   },
   "dependencies": {